180 



"jraiige of soutliorn foiius up the valleys of ouv streams is as though the 

 great spread tingers of two mighty hands were interlocked, the one rep- 

 resenting the extension of life southward and the other the projection of 

 ■••southern birds i:o;thward. 



The region of the Lower Wabash, with its bottoms, cypress swamps 

 tind ponds, was the home of many southern birds which found there the 

 northern limit of their range. Among these congenial surroiuidings Avere 

 noted such southern forms as the White Ibis (Guara alba). Wood Ibis 

 (Tautahis loculator). Yellow-crowned Night Heron (Nycticorax violaceus). 

 Little Blue Heron (Ardea csBruleal, Snowy Heron (Ardea candidiesima), 

 American Egret (Ardea egretta) and Florida Cormorant (Phalacrocorax 

 diloiihus floridanus). Some of these there made their homes and reared 

 their young. Other birds ranged farther up the stream and it, and other 

 water-courses, are now known to be routes along which certain species 

 move to breeding grounds farther north. 



The extreme effect of a river on the distribution of a Ijird is illustrated 

 in the case of the Prothonotary AVarbler. Prior to 1875, it was regarded 

 as solely a bird of the Southern States, yet its actual range was then, 

 without doubt, practically the same as we now know it. In that year 

 Mr. E. W. Nelson observed it to be common in the LoAver Wabash Valley 

 in Illinois (Bull. Essex Inst. Vol. IX. 1877. p. 34). In 1878, Mr. Will- 

 iam BreAvster found it abundant in Knox and Gibson counties, Indiana 

 (Bull. Nutt. Orn. Club, Vol. Ill, 1878. p. 155). The natural haunts of 

 these birds are the SAvampy Avoods and the thickets along water-courses 

 or about ponds or lakes. As one suitable locality after another Avas dis- 

 covered farther nortliAvard, it was found to be occupied by these bii'ds. 

 They were reported from Vigo, Clinton and Carroll counties and from 

 just over the State line near Danville, Illinois. They extended up the 

 Mississippi River, sending off numbers of migrants up the different river 

 courses. Some ascended the Kaskaskia and others the Illinois (Loucks 

 Bull. 111. Lab. N. II., Vol. IV, 1894). The Kankakee, a tributary of the 

 latter stream, comes into northwest Indiana from the west and becomes 

 quite a factor in its influence upon bird life. At Momence, Illinois, its 

 course is blocked by an outcrop of stone. Above this, it is a sluggish 

 stream, at times Avideuing into lakes. Much of its course Is bordered by 

 woods. Marshes and swamps alternate Avith thickets and sloughs along 

 its valley. Amid such attractive surroundings, Prothonotary Warblers 

 find summer quarters and are characteristic birds. Tliev likelv reach 



